Apparatus for feeding pulverized fuel.



I. E. BELL.

APPARATUS FOR FEEDING PULVERIZED FEL.

APPLICATION FILED IULY 29, 1914A I l L, Patented; May 23, MMI.

WITNESSES 1A E. BELL. APPARATUS FOR FEEDI'NG PULVERIZED FUEL.

APPLICATION FILD JULY 29, i914.,

Patented May 23,

5 SHEETS-SHEET 2.

-LLL I4 Il l INVENTOR WITH Pl l. E. BELL.

APPAR/uus Foa msnm@ PuLvEmzen FUEL.

APPL|CAT|0N FILED JULY 29| |914. l9,3 Patented May 23,1916.

5 SHEETS-SHEET 3.

WITNESSES INUENTOR J. E. BELL.

A APPARATUS FOR FEEDING PULVERIZED FUEL.

.` APPLIGATIVON FILED JULY 29, 1914 Patented May 23, 1916. l.

5 SHEETS-SHEET 5.

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JOHN E. BELL, OF NEW YORK, 1\T. Y.

APPARATUS FOR FEEDING PULVERIZED FUEL.

Specication of Letters Patent.

Patented May 23, 11916.

Application led July 29, 1914. Serial No. 853,827.

To all whom it may concern.'

Be it known that I, JoHN E. BELL, a citizen of the United States,residing at New York, in the county of New York and State of N ew York,have invented a new and useful Improvement in Apparatus for FeedingPulver-ized Fuel, of which the following is a full, clear, and exactdescription, refer ence being had to the accompanying drawings, formingpart of this specification, in which*- 4 Figure 1 is a plan view of a.portion of a furnace structure embodying my invention; Fig. 2 is alongitudinal vertical section taken, for instance, on the line H--II ofFig. 1; Fig. 3 is a transverse vertical section taken on the lineIII--HI of Figs. 1 and 2; Fig. d is a vertical section taken through oneof the feeders on the line IV-IV of Fig. 3; Fig. 5 is a section on theirregular line V-V of Fig. 2; and Fig. 6 is aI sectional plan view of aportion of the struc' ture.

The object of my invention is to provide apparatus for feedingpulverized fuel which will deliver the particles of fuel in such amanner as to cause them to be thoroughly mixed with air before they passinto the combustion chamber. I also preferably provide regenerator meansfor furnishing a supply of preheated air for mixing with the fueldelivered by the feeding apparatus and whereby the spent productsofcoiib-ustion may be utilized for preheating tlii's air.

lVhile I have shown my inventiiras apl' d to a boiler furnace a d more*articu- P 1e i Il .i `P larly to a boiler of the return tubular type, myinvention is not limited in its application to any particular type'offurnace, but is applicable to various types of boiler furnaces, to gasproducers and open hearth furnaces, and in fact, wherever it is desiredto use pulverized fuel.

`ln the accompanying drawings. the numeral 2 designates the wall of thefurnace structure; and 3 the filles which extend above the combustionchamber 4, and open at one end into` the vertical chamber 5 and at theopposite end-into an oiitake 6.

The numeral V7 ldesignates a hopper into which. the granulated orpulverized fuel may be'vfedv, this hopper opening at the bottom intoafeeding chamber 8, which eX- tends transversely across the front of thefurnace in front of the otftake 6.

9 is a screw conveyer working in the chamber 8, and adapted to feed thefuel lon*- gitudinally therethrough. The bottom of the chamber 8 isprovided at intervals With discharge spouts 10, each of which isarranged to discharge into a xed hopper 11, and having a fuel-measuringdevice 12, working therein. i

The portion 1la of the hopper 11, in which the measuring device works,has a contracted discharge opening 13, which is arranged to deliver thefuel into the funnel-shaped portion of an oscillating hopper anddistributer 14. This oscillating distributer is arranged to work withinthe'downwardly enlarged opening l5 of a watencooled member 16, setwithin the wall of the furnace structure. The shaft of thc/conveyor 9may be driven in any suitable manner. t is shown as having a pulley 17,connected by a belt 17 with a driving shaft 18. The conveyer shaft has adriving connection at 18a with a shaft 19, from which a series ofdriving connections :20 extend to pulleys 21 on the ends of the shafts2:2 of the fuel measuring devices 12. The oscillating fuel distributers14 may also be actuated in any suitable manner, as by the-rods Q8, eachof which is connected to one of said distributers and also to the strapQ4 of an eccentric A series of these eccentrics is placed on the shaft26. which is also shown as being driven by a belt 27. from the drivingshaft 18. The distributers 14 are arranged to discharge the fuel as theyoscillate. into a mixing chamber 2S, which communicates with thecombustion chamber 4 over the bridge wall 29.

8 0 designates a series of vent openings normally closed by theexplosion caps 31.

Each of the discharge chutes 10 may be provided with a regulating valve10a, shown in Fig. Je. The bottom wall of the combustion chamber 4 hasone or more openings 3Q. extending therethrough and leading into asecondary chamber 33. The opening 32 forms what I term a vortex mixer.The Chamber 83 communicates by one or more openings 34 with the chamber5, into which the rear ends of the fiues 3 open.

The otftake pipe G has the two branches 35 and 221%. leading`respectively, to the regenerators 37 and 38. 39 is a valve forcontrolling the flow of gases from the offtake to these regenerators,(sce Fig. 5). Each regenerator has an :Tir inlet opening 40, controlledby a valve 41. These valves may be opening so arranged, as shown in Fig.6, that when either one is open to admit air to the regenerator, itcloses the outlet from the regenerator to the stack passage l2. Eachregenerator also has a connection e3, leading into the mixing chamber28, and provided with a controlling valve #l-l.

The operation is as follows: The fuel is fed into the mixing chamber 2 8in the front extension of the furnace in the manner before described.The air supply coming in to this chamber from one of the regeneratorsthrough the connection i3, rises and meets the stream of granulated fuelwith which it mixes'and passes out over the bridge wall :29, into thecombustion chamber fl. The lower portion of the chamber 28, below thebridge wall 29,`forms a space for catching any heavier particles of fuelwhich may fall through the current of air. The combustion chamber 4.-includes the space which is ordinarily included between the grates andthe water-heating surface. In accordance with my invention, however, nogrates -are used. The burning fuel, after ignition, may pass towater-heating surfaces in any suitable manner. ture shown, the space atthe rear Aend of the combustion chamber isentirely closed off by thebridge wall 4a, and the gases and unconsumed fuel are compelled to passdownwardly through the opening or openings 32 in the floor vof saidchamber. The or openings being of restricted cross section, a highvelocity of theigases will take place in passing through such opening oropenings, this resulting in a very complete mixture of the air-,fuel andgases, the action being in the nature of a vortex. For.

this purpose, the furnace may be used with a strong draft.

The gases of combustion being thoroughly intermingled in passing throughthe opening or openings, all inflammable matter con- Y, tained thereinwill be consumed 1n the secondary combustion chamber 33. From thissecondary combustion chamber the gases pass through the boiler in theregular way, and thence to the regenerators 37 .and 38. Theseregenerators may consist of cylinders lined with firebrick and built ofcheckerwork. The gases 0f combustion-from the boiler pass through one ofthe regenerators, while thel air for combustion comes in through theother, a reversal of the flowv taking place at suitable intervals and inthe usual way by means of the valve or dampers. From the regenerator,the gases` pass to the stack or induced draft end of the furnace. Byfeeding the coal in the manner described through the oscillatingdistributer spouts, the feed is largely by gravity assisted by thecentrifugal; force produced by the oscillation of the spouts. Thismethod of feeding gives a uniform distribution of In the particularstruc-- the fuel throughout the chamber 28, assuring a much bettermixture than' can be obtained by stationary feeders. This distributionis also greatly facilitated by dropp ing the fuel into an ascendingcurrent of air.

The extensive experiments ,and investigations which I have conductedshow that perfect combustion of pulverized or granulated fuel is verylargely a question of mechanical mixture. My experiments show' that ahot gas acts very much in the nature of an extremely viscous fluid, andthat it has very little tendency to a mixing action.

It is therefore important that some meansV as abOVe described vinsuresto ar still greater) -degree the obtaining of a very high degree ofcombustion. Myxinvention is not,.however, dependent upon the use of theeddy flow through the vortex mixer and, in fact,

can be efficiently operated without this feature.

Features of my invention" not claimedY herein are in the subject matterof my divisional application, Serial June 7, 1915.

I claim:

No. 32,540, 1aed 1. Apparatus for feeding pulverized granulated fuel',comprising a mixing chamrber, a spout pivoted to `oscillate ma verticalplane at the upper portion of the mixing chamber, means for deliveringpulverized or granular fuel thereto, means for oscillating the spout to'deliver the particles into the mixing chamber, and means for supplyingan upwardly and laterally moving current of air into which the fuelparticles are discharged zfrom said spout, substantial-ly as described.

2. Apparatus for feeding pulverized or granulated fuel, comprising afurnace structure having a combustion chamber and a mixing chamber inadvance of the combustion chamber, an oscillating fuel delivery membermounted po swing in a vertical plane and'discharge into the mixingchamber, and means for maintaining a moving body of air into which thefuel particles are discharged and by which they are carried into thecombustion chamber, substantially as""described. i y y 3.`Apparatus forfeeding pulverized or granulated fuel, comprising a furnace. structurehaving a combustion chamber and'a mixing chamber in advance of the com,-bustion chamber, an oscillating fuel delivery member mounted to swing ina vertical ber, and means for openings, a mixing chamber below thefeeder v `and which communicates With a combustion chamber, anoscillating fu'el distributerbelow each discharge opening of. thefeeder, i

; Witnesses: v i

and arranged to discharge into the mixing chamber, and means forproviding a moving body of air into which the fuel is discharged by thedistributers and by which it is carried into the combustion chamber,substantially as described. I In vtestimony whereof, 'I have 1- hereunto20 set my hand.

JOHN E. BELL.

JESSE B. HELLER, t 1 M. CoRwIN.

